Important Developments in Burn Care

Revalidating the prognostic relevance of the Abbreviated Burn Severity Index (ABSI): A twenty-year experience examining the performance of the ABSI score in consideration of progression and advantages of burn treatments from a single center in Vienna

BACKGROUND

The Abbreviated Burn Severity Index (ABSI) is a five-variable scale to help evaluate burn severity upon initial assessment. As other studies have been conducted with comparatively small patient populations, the purpose of this study is to revalidate the prognostic relevance of the ABSI in our selected population (N = 1193) 4 decades after its introduction, considering the progress in the treatment of severe burn injuries over the past decades. In addition, we evaluate whether comorbidities influence the survival probability of severely burned patients.

METHODS

This retrospective study presents data from the Center for Severely Burned Patients of the General Hospital in Vienna. We included 1193 patients for over 20 years. Regression models were used to describe the prognostic accuracy of the ABSI.

RESULTS

The ABSI can still be used as a prognostic factor for the probability of survival of severely burned patients. The odds of passing increases by a factor of 2.059 for each unit increase in the ABSI with an area under the curve value of 0.909. Over time, the likelihood of survival increased. The existence of chronic kidney disease negatively impacts the survival probability of severely burned patients.

CONCLUSION

The ABSI can still be used to provide accurate information about the chances of survival of severely burned patients; however, further exploration of the impact of chronic kidney disease on the survival probability and adding variables to the ABSI scale should be considered. The probability of survival has increased over the last 20 years.

Analysis of bioprinting strategies for skin diseases and injuries through structural and temporal dynamics: historical perspectives, research hotspots, and emerging trends

This study endeavors to investigate the progression, research focal points, and budding trends in the realm of skin bioprinting over the past decade from a structural and temporal dynamics standpoint. Scholarly articles on skin bioprinting were obtained from WoSCC. A series of bibliometric tools comprising R software, CiteSpace, HistCite, and an alluvial generator were employed to discern historical characteristics, evolution of active topics, and upcoming tendencies in the area of skin bioprinting. Over the past decade, there has been a consistent rise in research interest in skin bioprinting, accompanied by an extensive array of meaningful scientific collaborations. Concurrently, diverse dynamic topics have emerged during various periods, as substantiated by an aggregate of 22 disciplines, 74 keywords, and 187 references demonstrating citation bursts. Four burgeoning research subfields were discerned through keyword clustering-namely, #3 'in situbioprinting', #6 'vascular', #7 'xanthan gum', and #8 'collagen hydrogels'. The keyword alluvial map reveals that Module 1, including 'transplantation' etc, has primarily dominated the research module over the previous decade, maintaining enduring relevance despite annual shifts in keyword focus. Additionally, we mapped out the top six key modules from 2023 being 'silk fibroin nanofiber', 'system', 'ionic liquid', 'mechanism', and 'foot ulcer'. Three recent research subdivisions were identified via timeline visualization of references, particularly Clusters #0 'wound healing', #4 'situ mineralization', and #5 '3D bioprinter'. Insights derived from bibliometric analyses illustrate present conditions and trends in skin bioprinting research, potentially aiding researchers in pinpointing central themes and pioneering novel investigative approaches in this field.

A novel skin grafting modality: prefabricated large sheet of postage-stamp autografts and allografts to repair extensive burn wounds; a prospective matched-control study

BACKGROUND

The excessively long operative time has been the greatest barrier to the success of transplanting postage-stamp auto- and allografts directly and piece-by-piece onto extensive burn wounds. To solve this challenge, the authors present a novel grafting modality, that is, the prefabricated-large-sheet grafting that moves the labor-intensive and time-consuming process of grafts-positioning before grafting and thereby markedly shortens the operative time.

METHODS

Twenty-one operations using the novel modality were performed on 11 patients with extensive deep burns. The grafting time using the novel modality was recorded and compared with that of the conventional piece-by-piece grafting. Eventually, the take rates of the two modalities were compared.

RESULTS

All patients were healed and discharged. The average grafting time per unit area (100 cm2) of prefabricated-large-sheet grafting and piece-by-piece grafting were (0.41±0.09) min and (7.46±1.07) min, respectively, and the difference is statistically significant(P<0.001). The average take rate of the prefabricated sheets was (85.43±6.14)% and that of the piece-by-piece transplanted grafts was (87.29±5.23)% and there is no significant difference(P>0.05).

CONCLUSIONS

The prefabricated-large-sheet grafting significantly reduces the intraoperative grafting time while ensures uniformity of the skin grafts and secures good outcomes, thereby making the intermingled transplantation of postage-stamp auto- and allografts, which has been an excellent modality per se but limited to repair small residual wounds, now feasible to repair extensive deep burn wounds. It is worth wider understanding and application in the treatment of extensive deep burns.

Scars

Wound healing occurs as a response to disruption of the epidermis and dermis. It is an intricate and well-orchestrated response with the goal to restore skin integrity and function. However, in hundreds of millions of patients, skin wound healing results in abnormal scarring, including keloid lesions or hypertrophic scarring. Although the underlying mechanisms of hypertrophic scars and keloid lesions are not well defined, evidence suggests that the changes in the extracellular matrix are perpetuated by ongoing inflammation in susceptible individuals, resulting in a fibrotic phenotype. The lesions then become established, with ongoing deposition of excess disordered collagen. Not only can abnormal scarring be debilitating and painful, it can also cause functional impairment and profound changes in appearance, thereby substantially affecting patients' lives. Despite the vast demand on patient health and the medical society, very little progress has been made in the care of patients with abnormal scarring. To improve the outcome of pathological scarring, standardized and innovative approaches are required.

Autonomous Multi-modality Burn Wound Characterization using Artificial Intelligence

INTRODUCTION

Between 5% and 20% of all combat-related casualties are attributed to burn wounds. A decrease in the mortality rate of burns by about 36% can be achieved with early treatment, but this is contingent upon accurate characterization of the burn. Precise burn injury classification is recognized as a crucial aspect of the medical artificial intelligence (AI) field. An autonomous AI system designed to analyze multiple characteristics of burns using modalities including ultrasound and RGB images is described.

MATERIALS AND METHODS

A two-part dataset is created for the training and validation of the AI: in vivo B-mode ultrasound scans collected from porcine subjects (10,085 frames), and RGB images manually collected from web sources (338 images). The framework in use leverages an explanation system to corroborate and integrate burn expert's knowledge, suggesting new features and ensuring the validity of the model. Through the utilization of this framework, it is discovered that B-mode ultrasound classifiers can be enhanced by supplying textural features. More specifically, it is confirmed that statistical texture features extracted from ultrasound frames can increase the accuracy of the burn depth classifier.

RESULTS

The system, with all included features selected using explainable AI, is capable of classifying burn depth with accuracy and F1 average above 80%. Additionally, the segmentation module has been found capable of segmenting with a mean global accuracy greater than 84%, and a mean intersection-over-union score over 0.74.

CONCLUSIONS

This work demonstrates the feasibility of accurate and automated burn characterization for AI and indicates that these systems can be improved with additional features when a human expert is combined with explainable AI. This is demonstrated on real data (human for segmentation and porcine for depth classification) and establishes the groundwork for further deep-learning thrusts in the area of burn analysis.

The Use of Laser Doppler Imaging in Nitric Acid Burns: A Case Report and Literature Review

Laser Doppler imaging (LDI) technology has been validated to assess thermal burn depth by predicting wound healing potential. However, there is no clear evidence for its use in chemical burns. We present a case of an 8% total burn surface area (TBSA) nitric acid burn following an industrial accident, in an otherwise healthy 36-year-old man. LDI assessment was suggestive of poor healing potential of >21 days, warranting surgical management. However, conservative management was opted for based on clinical assessment as the wound eschar appeared thin and more consistent with epithelial staining. Patient follow-up confirmed a total burn healing time of two months, suggesting that the LDI assessment was accurate. A comprehensive literature review was performed using the MEDLINE (PubMed) database to identify animal or clinical studies evaluating the efficacy of LDI in chemical burns. A qualitative synthesis of our findings is presented. We identified two experimental studies in porcine models with sulfur mustard burns, each confirming the accuracy of LDI assessment when compared to the histopathology findings. Limited experimental animal studies on the use of LDI suggest similar validity in chemical burns, and this correlates with the clinical outcome in this case. However, this alone is insufficient to prove its validity and define its role in the assessment of chemical burns. Clinical trials are required to further assess and define the parameters of LDI use and efficacy in this context.

Psychiatric Illness and Substance Abuse: Unaddressed Factors in Burn Injury

Patients with psychiatric illness and substance use comorbidities have high rates of burn injuries and experience prolonged hospital admissions. This retrospective chart review characterizes this marginalized population's inpatient burn care and examines post-discharge outcomes compared to burn patients without psychiatric or substance use comorbidities treated at our center. Patients admitted to a single burn center from January 1, 2018 to June 1, 2022 were included. Patient demographics, history of psychiatric disorders, treatment course, and post-discharge outcomes were collected. A total of 1660 patients were included in this study, of which 91 (6%) patients were diagnosed for psychiatric comorbidity and/or substance use comorbidity on admission for burn care. In this cohort of 91 patients with psychiatric and/or substance use comorbidities, the majority of patients were undomiciled (66%) and male (67%). In this cohort, 66 (72%) patients reported recent history or had positive urine toxicology results for illicit substances on admission. In this cohort, a total of 25 (28%) patients had psychiatric comorbidity at the time of burn injury or admission and 69 (76%) patients received inpatient psychiatric care, with 31 (46%) patients requiring psychiatric holds. After discharge, the readmission rate within 1 year of patients with psychiatric and/or substance use comorbidity was over four times greater than that of patients without psychiatric and/or substance use comorbidity. The most common causes of readmission were subsequent mental health crisis (40%) and inability to perform burn care (32%). Our study presents strategies to improve burn care for this marginalized and high-risk population.

Tilapia Fish Skin Treatment of Third-Degree Skin Burns in Murine Model

This study explored the feasibility of using fish skin bandages as a therapeutic option for third-degree skin burns. Following the California wildfires, clinical observations of animals with third-degree skin burns demonstrated increased comfort levels and reduced pain when treated with tilapia fish skin. Despite the promises of this therapy, there are few studies explaining the healing mechanisms behind the application of tilapia fish skin. In this study, mice with third-degree burns were treated with either a hydrocolloid adhesive bandage (control) (n = 16) or fish skin (n = 16) 7 days post-burn. Mice were subjected to histologic, hematologic, molecular, and gross evaluation at days 7, 16, and 28 post-burn. The fish skin offered no benefit to overall wound closure compared to hydrocolloids. Additionally, we detected no difference between fish skin and control treatments in regard to hypermetabolism or hematologic values. However, the fish skin groups exhibited 2 times more vascularization and 2 times higher expression of antimicrobial defensin peptide in comparison to controls. Proteomic analysis of the fish skin revealed the presence of antimicrobial peptides. Collectively, these data suggest that fish skin can serve as an innovative and cost-effective therapeutic alternative for burn victims to facilitate vascularization and reduce bacterial infection.

Novel Design and Implementation of an Integrated Burn Rehabilitation Clinical Fellowship

ABSTRACT

Postgraduate medical burn rehabilitation training has been limited, with very few academic physiatrists specializing in burn rehabilitation. As a result, there are no existing models for postgraduate burn rehabilitation education. A 12-mo comprehensive clinical fellowship in burn rehabilitation was offered through a tertiary burn center with formal university accreditation. In this article, the clinical, educational, and skill-based goals developed and implemented for this novel fellowship was outlined to serve as a blueprint for future fellowships in burn rehabilitation, as well as reflections on the experience.

Global Disparities in Burn Outcomes: Does Gender Predict Mortality in the Global Burn Registry?

INTRODUCTION

Global burn injury burden disproportionately impacts low- and middle-income countries. Surgery is a mainstay of burn treatment, yet access to surgical care appears to be inequitably distributed for women. This study sought to identify gender disparities in mortality and access to surgery for burn patients in the World Health Organization Global Burn Registry (GBR).

METHODS

We queried the World Health Organization GBR for a retrospective cohort (2016-2021). Patients were stratified by sex. Outcomes of interest were in-hospital mortality and surgical treatment. Patient demographics, injury characteristics, outcomes, and health facility resources were compared between sexes with Wilcoxon rank sum test for nonparametric medians, and chi-squared or Fisher's exact test for nonparametric proportions. Multivariable logistic regressions were performed to assess the relationships between sex and mortality, and sex and surgery.

RESULTS

Of 8445 patients in the GBR from 20 countries (10 low resource), 40% of patients were female, with 51% of all patients receiving surgical treatment during their hospitalization. Female patients had a higher incidence of mortality (24% versus 15%, P < 0.001) and a higher median total body surface area (20% versus 15%, P < 0.001), yet a lower incidence of surgery (47% versus 53%, P < 0.001) following burn injury when compared to males. In multivariable analysis, female sex was independently associated with mortality after controlling for age, time to presentation, smoke injury, percent total body surface area, surgery, and country income status. Female sex was independently associated with surgical care (odds ratio 0.86, P = 0.001).

CONCLUSIONS

Female burn patients suffer higher mortality compared to males and are less likely to receive surgery. Further study into this gender disparity in burns is warranted.

Robot-assisted in situ bioprinting of gelatin methacrylate hydrogels with stem cells induces hair follicle-inclusive skin regeneration

Large skin defects caused by accidents or disease can cause fluid loss, water and electrolyte disorders, hypoproteinemia and serious infection and remain a difficult problem in clinical practice. In situ bioprinting is a promising, recently developed technology that involves timely, customized, and morphologically adapted bioprinting of bioink into tissue defects to promote the recovery of human tissues or organs. During this process, bioink is a key factor. In this study, we synthesized a biocompatible, photosensitive hydrogel material comprising gelatin methacrylate (GelMA) for robot-assisted in situ bioprinting of skin wounds. The results showed that GelMA demonstrated good printability of that supported the proliferation of skin-derived precursors (SKPs) and maintained their properties. Furthermore, in situ bioprinting of GelMA hydrogels with epidermal stem cells (Epi-SCs) and SKPs onto skin wounds showed complete wound healing and functional tissue skin regeneration. The regenerated skin contains epidermis, dermis, blood vessels, hair follicles, and sebaceous glands and resembling native skin. These results provide an effective strategy for skin repair through the combined application of GelMA hydrogels, Epi-SCs, SKPs and in situ bioprinting and its promising clinical translational potential for further applications.

Risk Models to Predict Mortality in Burn Patients: A Systematic Review and Meta-analysis

The predictive capability of various risk assessment models (RAMs) in evaluating the risk of mortality in burn patients is not well established. It is also unclear which RAM provides the highest discriminative ability and presents the highest clinical utility. We pooled all available studies to establish this validity and compare the predictive capability of the various RAMs.

Methods

We reviewed PubMed, MEDLINE, and Embase from their inception up until December 2021 for studies evaluating risk of mortality in burn patients as stratified by RAMs. Data were pooled using random-effect models and presented as area under the receiver operating characteristic (AUROC) curve.

Results

Thirty-four studies, comprising of a total of 98,610 patients, were included in our analysis. Most studies were found to have a low risk of bias and a good measure of applicability. Nine RAMs were evaluated. We discovered that the classic Baux; the revised Baux; and the Fatality by Longevity, APACHE II score, Measured Extent of burn, and Sex (FLAMES) scores presented with the highest discriminative power with there being no significant difference between the results presented by them [AUROCs (95% CI), 0.92 (0.90-0.95), 0.92 (0.90-0.93), 0.94 (0.91-0.97), respectively, with P < 0.00001 for all].

Conclusions

Many RAMs exist with no consensus on the optimal model to utilize and assess risk of mortality for burn patients. This study is the first systematic review and meta-analysis to compare the current RAMs' discriminative ability to predict mortality in patients with burn injuries. This meta-analysis demonstrated that RAMs designed for assessing mortality in individuals with burns have acceptable to great discriminative capacity, with the classic Baux, revised Baux, and FLAMES demonstrating superior discriminative performance in predicting death. FLAMES exhibited the highest discriminative ability among the RAMs studied.

Objective Burn Scar Assessment in Clinical Practice Using the Cutometer©: Introduction and Validation of a Standardized Measurement Protocol

An objective burn scar assessment is essential to informed therapeutic decision-making and to monitor scar development over time. However, widely employed scar rating scales show poor inter-rater reliability. For this study we developed a standardized measurement protocol for the Cutometer© applicable for objective burn scar assessment in everyday clinical practice. We developed a measurement protocol for the Cutometer© MPA 580 including a scar site relocation technique based on anatomical landmarks. The protocol emerged through several steps: Identifying key factors for valid and reliable measurements, preliminary testing, specification of technical details, refining the protocol and final testing. Consecutively, the protocol was validated for inter-rater reliability by assessing 34 burn scars in 17 patients by four clinicians and computing an Intra-class Correlation Coefficient (ICC). Parameter R0, representing scar pliability, was identified as the best suited output parameter yielding excellent inter-rater reliability for average measures (ICC 0.92 [95% CI 0.86; 0.96]) and acceptable reliability for single measures (ICC: 0.74 [0.61; 0.84]). The pressure applied on the measuring probe was identified as an influential confounding factor for reliable measurements. Rater gender did not influence reliability of measurements. The introduced standardized measurement protocol for the Cutometer© MPA 580 enables an objective and reliable burn scar assessment for clinical as well as research purposes.

Adipose stromal vascular fraction: a promising treatment for severe burn injury

Thermal skin burn injury affects both adults and children globally. Severe burn injury affects a patient's life psychologically, cosmetically, and socially. The pathophysiology of burn injury is well known. Due to the complexity of burn pathophysiology, the development of specific treatment aiding in tissue regeneration is required. Treatment of burn injury depends on burn severity, size of the burn and availability of donor site. Burn healing requires biochemical and cellular events to ensure better cell response to biochemical signals of the healing process. This led to the consideration of using cell therapy for severe burn injury. Adult mesenchymal stem cells have become a therapeutic option because of their ability for self-renewal and differentiation. Adipose stromal vascular fraction (SVF), isolated from adipose tissues, is a heterogeneous cell population that contains adipose-derived stromal/stem cells (ADSC), stromal, endothelial, hematopoietic and pericytic lineages. SVF isolation has advantages over other types of cells; such as heterogeneity of cells, lower invasive extraction procedure, high yield of cells, and fast and easy isolation. Therefore, SVF has many characteristics that enable them to be a therapeutic option for burn treatment. Studies have been conducted mostly in animal models to investigate their therapeutic potential for burn injury. They can be used alone or in combination with other treatment options. Treatment with both ADSCs and/or SVF enhances burn healing through increasing re-epithelization, angiogenesis and decreasing inflammation and scar formation. Research needs to be conducted for a better understanding of the SVF mechanism in burn healing and to optimize current techniques for enhanced treatment outcomes.

Montelukast, an Antagonist of Cysteinyl Leukotriene Signaling, Impairs Burn Wound Healing

BACKGROUND

Burns are severe injuries often associated with impaired wound healing. Impaired healing is caused by multiple factors, including dysregulated inflammatory responses at the wound site. Interestingly, montelukast, an antagonist for cysteinyl leukotrienes and U.S. Food and Drug Administration approved for treatment of asthma and allergy, was previously shown to enhance healing in excision wounds and to modulate local inflammation.

METHODS

In this study, the authors examined the effect of montelukast on wound healing in a mouse model of scald burn injury. Burn wound tissues isolated from montelukast- and vehicle-treated mice at various times after burn injury were analyzed for wound areas ( n = 34 to 36), reepithelialization ( n = 14), inflammation ( n = 8 to 9), and immune cell infiltration ( n = 3 to 6) and proliferation ( n = 7 to 8).

RESULTS

In contrast to previously described beneficial effects in excision wounds, this study shows that montelukast delays burn wound healing by impairing the proliferation of keratinocytes and endothelial cells. This occurs largely independently of inflammatory responses at the wound site, suggesting that montelukast impairs specifically the proliferative phase of wound healing in burns. Wound healing rates in mice in which leukotrienes are not produced were not affected by montelukast.

CONCLUSION

Montelukast delays wound healing mainly by reducing the proliferation of local cells after burn injury.

CLINICAL RELEVANCE STATEMENT

Although additional and clinical studies are necessary, our study suggests that burn patients who are on montelukast may exhibit delayed healing, necessitating extra observation.

Impact of the Early COVID-19 Pandemic on Burn Care: A Multi-National Study

This qualitative study documents and analyzes COVID-19’s impacts on burn care in twelve nations. Burn care saw valuable improvements in surgical techniques, skin grafting, and other acute treatments during the decades before the COVID-19 pandemic which increased severely burned patients’ survival rates and quality of life. Detailed interviews, conducted in the 12 nations reveal that the COVID-19 pandemic greatly affected the delivery of acute and rehabilitation services for burn patients. Resources have been suctioned away from non-COVID healthcare and burn care has not been spared. Acute, post-acute rehabilitation, and mental health services have all suffered. Weak preparation has deeply burdened health care services in most nations, resulting in lower access to care. Access problems have accelerated innovations like telehealth in many nations. The spread of misinformation through social and traditional media has contributed to the varied responses to COVID-19. This compounded problems in health care delivery. Burn care providers delivered services for survivors during extremely difficult circumstances by continuing to furnish acute and long-term services for patients with complex disease. Emphasis on future pandemic preparedness will be vital because they undermine all aspects of burn care and patient outcomes. As the COVID-19 pandemic continues to unfold around the world, it will be important to continue to monitor and analyze the adaptability of nations, health care systems, and burn care providers.

A Systematic Review and Meta-Analysis of Extracorporeal Membrane Oxygenation in Patients with Burns

BACKGROUND

Severely burned patients are at high risk for cardiopulmonary failure. Promising studies have stimulated interest in using extracorporeal membrane oxygenation as a potential therapy for burn patients with refractory cardiac and/or respiratory failure. However, the findings from previous studies vary.

METHODS

In this study, the authors conducted a systematic review and meta-analysis using standardized mortality ratios to elucidate the benefits associated with the use of extracorporeal membrane oxygenation in patients with burn and/or inhalation injuries. A literature search was performed, and clinical outcomes in the selected studies were compared.

RESULTS

The meta-analysis found that the observed mortality was significantly higher than the predicted mortality in patients receiving extracorporeal membrane oxygenation (standardized mortality ratio, 2.07; 95 percent CI, 1.04 to 4.14). However, the subgroup of burn patients with inhalation injuries had lower mortality rates compared to their predicted mortality rates (standardized mortality ratio, 0.95; 95 percent CI, 0.52 to 1.73). Other subgroup analyses reported no benefits from extracorporeal membrane oxygenation; however, these results were not statistically significant. Interestingly, the pooled standardized mortality ratio values decreased as the selected patients' revised Baux scores increased (R = -0.92), indicating that the potential benefits from the treatment increased as the severity of patients with burns increased.

CONCLUSIONS

The authors' meta-analysis revealed that burn patients receiving extracorporeal membrane oxygenation treatment were at a higher risk of death. However, select patients, including those with inhalation injuries and those with revised Baux scores over 90, would benefit from the treatment. The authors suggest that burn patients with inhalation injuries or with revised Baux scores exceeding 90 should be considered for the treatment and early transfer to an extracorporeal membrane oxygenation center.

Comparing the Efficiency of Tumescent Infiltration Techniques in Burn Surgery

Tangential excision and grafting of burn wounds result in significant intraoperative blood loss, and infiltration of a dilute epinephrine solution (tumescence) is routinely performed to reduce such bleeding. Tumescent infiltration has been described using both a manual technique (syringe) and a pump device. The purpose of this study is to compare the efficiency of these two methods in terms of time and economy of motion. Consecutive adult burn patients at a single center requiring excision and grafting were enrolled in the study and randomized into either the manual or pump technique. Excisions involving less than 2% TBSA were excluded, along with specific anatomic regions (eg, head and neck). Infiltration with epinephrine solution (1:500,000) was performed to the endpoint of tumescence by a single surgeon and filmed/coded for duration, number of maneuvers, and volume of tumescence injected. Fourteen patients were enrolled, and 16 cases were randomized to either manual (N = 8) or pump infiltration (N = 8). The pump method required less time (2.0 vs 1.1 cm2/s, P < .001) and fewer maneuvers (37.8 vs 1.1 cm2/move, P < .001) to reach the desired endpoint of tumescence. Use of the infiltration pump also resulted in a reduced volume of tumescent fluid required to reach this point of tumescence (1.7 vs 2.4 mL/cm2, P = .01). Compared to the manual technique, an infiltration pump was significantly more efficient in terms of both time and economy of motion. These reductions are potentially useful for improving operating room efficiency as well as minimizing operator fatigue.

Biomaterials-Based Regenerative Strategies for Skin Tissue Wound Healing

Skin tissue wound healing proceeds through four major stages, including hematoma formation, inflammation, and neo-tissue formation, and culminates with tissue remodeling. These four steps significantly overlap with each other and are aided by various factors such as cells, cytokines (both anti- and pro-inflammatory), and growth factors that aid in the neo-tissue formation. In all these stages, advanced biomaterials provide several functional advantages, such as removing wound exudates, providing cover, transporting oxygen to the wound site, and preventing infection from microbes. In addition, advanced biomaterials serve as vehicles to carry proteins/drug molecules/growth factors and/or antimicrobial agents to the target wound site. In this review, we report recent advancements in biomaterials-based regenerative strategies that augment the skin tissue wound healing process. In conjunction with other medical sciences, designing nanoengineered biomaterials is gaining significant attention for providing numerous functionalities to trigger wound repair. In this regard, we highlight the advent of nanomaterial-based constructs for wound healing, especially those that are being evaluated in clinical settings. Herein, we also emphasize the competence and versatility of the three-dimensional (3D) bioprinting technique for advanced wound management. Finally, we discuss the challenges and clinical perspective of various biomaterial-based wound dressings, along with prospective future directions. With regenerative strategies that utilize a cocktail of cell sources, antimicrobial agents, drugs, and/or growth factors, it is expected that significant patient-specific strategies will be developed in the near future, resulting in complete wound healing with no scar tissue formation.

Evaluation of hyperspectral imaging as a modern aid in clinical assessment of burn wounds of the upper extremity

The most common burn wound assessment continues to be the clinical inspection and the tactile examination, which are subjective and remain challenging even for experienced burn surgeons. Recently, hyperspectral imaging camera systems have been increasingly used to support the evaluation of burn wounds. The aim of our study was to determine if hyperspectral imaging analysis differentiates and objectifies the assessment of burn wounds in burns of the upper extremities. We included 97 superficial partial, deep partial dermal burns, and full thickness burns. Hyperspectral imaging analysis was performed for all burns using proprietary software. The software recorded parameters for tissue oxygenation (StO2), tissue hemoglobin index, and near-infrared perfusion. These values were compared with the recordings for healthy, non-burned skin. We found that hyperspectral imaging analysis effectively differentiates burn wounds and shows the ability to distinguish even superficial partial burns from deep partial burns in the near-infrared perfusion analysis feature. Although, it was not possible to differentiate burn wounds in all features. Currently, it is important to optimize the respective reference values of the individual burn degrees for an objectified assessment.

Adaptive multi‐degree‐of‐freedom in situ bioprinting robot for hair‐follicle‐inclusive skin repair: A preliminary study conducted in mice

Skin acts as an essential barrier, protecting organisms from their environment. For skin trauma caused by accidental injuries, rapid healing, personalization, and functionality are vital requirements in clinical, which are the bottlenecks hindering the translation of skin repair from benchside to bedside. Herein, we described a novel design and a proof‐of‐concept demonstration of an adaptive bioprinting robot to proceed rapid in situ bioprinting on a full‐thickness excisional wound in mice. The three‐dimensional (3D) scanning and closed‐loop visual system integrated in the robot and the multi‐degree‐of‐freedom mechanism provide immediate, precise, and complete wound coverage through stereotactic bioprinting, which hits the key requirements of rapid‐healing and personalization in skin repair. Combined with the robot, epidermal stem cells and skin‐derived precursors isolated from neonatal mice mixed with Matrigel were directly printed into the injured area to replicate the skin structure. Excisional wounds after bioprinting showed complete wound healing and functional skin tissue regeneration that closely resembling native skin, including epidermis, dermis, blood vessels, hair follicles and sebaceous glands etc. This study provides an effective strategy for skin repair through the combination of the novel robot and a bioactive bioink, and has a promising clinical translational potential for further applications.

3D Printing: Advancement in Biogenerative Engineering to Combat Shortage of Organs and Bioapplicable Materials

Abstract

Organ or cell transplantation is medically evaluated for end-stage failure saving or extending the lives of thousands of patients who are suffering from organ failure disorders. The unavailability of adequate organs for transplantation to meet the existing demand is a major challenge in the medical field. This led to day-day-increase in the number of patients on transplant waiting lists as well as in the number of patients dying while on the queue. Recently, technological advancements in the field of biogenerative engineering have the potential to regenerate tissues and, in some cases, create new tissues and organs. In this context, major advances and innovations are being made in the fields of tissue engineering and regenerative medicine which have a huge impact on the scientific community is three-dimensional bioprinting (3D bioprinting) of tissues and organs. Besides this, the decellularization of organs and using this as a scaffold for generating new organs through the recellularization process shows promising results. This review discussed about current approaches for tissue and organ engineering including methods of scaffold designing, recent advances in 3D bioprinting, organs regenerated successfully using 3D printing, and extended application of 3D bioprinting technique in the field of medicine. Besides this, information about commercially available 3D printers has also been included in this article.

Lay Summary

Today's need for organs for the transplantation process in order to save a patient's life or to enhance the survival rate of diseased one is the prime concern among the scientific community. Recent, advances in the field of biogenerative engineering have the potential to regenerate tissues and create organs compatible with the patient's body. In this context, major advances and innovations are being made in the fields of tissue engineering and regenerative medicine which have a huge impact on the scientific community is three-dimensional bioprinting (3D bioprinting) of tissues and organs. Besides this, the decellularization of organs and using this as a scaffold for generating new organs through the recellularization process shows promising results. This review dealt with the current approaches for tissue and organ engineering including methods of scaffold designing, recent advances in 3D bioprinting, organs regenerated successfully using 3D printing, and extended application of 3D bioprinting technique in the field of medicine. Furthermore, information about commercially available 3D printers has also been included in this article.

Physical Rehabilitation and Mental Health Care after Burn Injury: A Multi-Nation Study

While remarkable improvements have been made to acute hospital burn care in recent decades, it is not matched by improvements in post-acute care, including physical rehabilitation and mental health. Progress in acute hospital treatment of burn survivors now highlights the next important step-addressing care once a patient leaves intensive treatment and is discharged to the community. Long-term physical rehabilitation and mental health services are vital to improving quality of life for burn survivors. Using qualitative methods, we apply the adapted Reeve framework to assess and compare post-acute physical rehabilitation and mental health care across thirteen countries on six continents. Twenty semi-structured interviews were conducted with burn surgeons and rehabilitation specialists. One major theme that emerged was the importance of training and resources to the quality of post-acute care. This exploratory study suggests the value of investing scarce resources in a range of low-cost interventions to improve follow-up burn care. One intervention identified here is short-term training in post-acute rehabilitation and mental health to upgrade and standardize best clinical practices to address as-yet unmet post-discharge needs of burn survivors.

Neutrophil-derived heparin binding protein triggers vascular leakage and synergizes with myeloperoxidase at the early stage of severe burns (With video)

Background

Burn shock caused by vascular leakage is one of the main causes of high mortality in severe burn injury. However, the pathophysiological mechanism of vascular leakage is still unclear. The purpose of this study was to explore the molecular mechanism of vascular leakage in the early stage of severe burn and provide a new target for the treatment of severe burns.

Methods

Neutrophils were isolated from human peripheral blood by magnetic beads sorting. ELISA was used to detect neutrophil-derived granule proteins and glycocalyx injury products in plasma. The vascular leakage and neutrophil movement were assessed by in vivo laser confocal imaging in mice, and high-quality video were provided.. Adhesion-related molecules were investigated by qRT-PCR. The damage to glycocalyx of mice vascular endothelial cells was observed by transmission electron microscope and scanning electron microscope. Proteomic analysis, flow cytometry and immunofluorescence were used to further study the relationship between human peripheral blood neutrophil-derived hypochlorite (HOCl) and CD44 of human vascular endothelial cells.

Results

In this study, we found that rapidly increasing activated neutrophils secrete heparin binding protein (HBP) and myeloperoxidase (MPO) after severe burn injury. Increased HBP triggers vascular leakage with synergy of MPO, results in systemic edema and burn shock. Furthermore, we found that the MPO catalytic product HOCl but not MPO triggers CD44 extracellular domain shedding from vascular endothelial cells to damage the glycocalyx. Damage to the glycocalyx results in firm adhesion of neutrophils and increases vascular leakage. However, MPO inhibitors partially protect the glycocalyx of vascular endothelial cells. The combination of HBP and MPO inhibitors markedly reduces vascular leakage and systemic edema in the early stage of severe burns.

Conclusions

Taken together, these data reveal that neutrophil-derived HBP and MPO play an important synergies role in triggering vascular leakage at the early stage of severe burns. Targeted intervention in these two biomolecules may introduce new strategies for helping to reduce large amount of fluid loss and subsequent burn shock.

The Role of DAMPS in Burns and Hemorrhagic Shock Immune Response: Pathophysiology and Clinical Issues. Review

Severe or major burns induce a pathophysiological, immune, and inflammatory response that can persist for a long time and affect morbidity and mortality. Severe burns are followed by a "hypermetabolic response", an inflammatory process that can be extensive and become uncontrolled, leading to a generalized catabolic state and delayed healing. Catabolism causes the upregulation of inflammatory cells and innate immune markers in various organs, which may lead to multiorgan failure and death. Burns activate immune cells and cytokine production regulated by damage-associated molecular patterns (DAMPs). Trauma has similar injury-related immune responses, whereby DAMPs are massively released in musculoskeletal injuries and elicit widespread systemic inflammation. Hemorrhagic shock is the main cause of death in trauma. It is hypovolemic, and the consequence of volume loss and the speed of blood loss manifest immediately after injury. In burns, the shock becomes evident within the first 24 h and is hypovolemic-distributive due to the severely compromised regulation of tissue perfusion and oxygen delivery caused by capillary leakage, whereby fluids shift from the intravascular to the interstitial space. In this review, we compare the pathophysiological responses to burns and trauma including their associated clinical patterns.

The Presence of Nucleated Red Blood Cells as an Indicator for Increased Mortality and Morbidity in Burn Patients

Nucleated red blood cells (NRBCs) have been studied in critically ill and injured patients as a predictor of increased in-hospital mortality and poor clinical outcomes. While prior studies have demonstrated the prognostic power of NRBCs in the critical patient, there has been a paucity of literature available describing their value as a prognostic indicator in the severely burned patient. This retrospective observational study was conducted from 2012 to 2017. Inclusion criteria for this study included all burn patients with total body surface area > 10% who were aged ≥ 15 years. Demographic and clinical data were collected from the electronic medical record system. Data analysis consisted of descriptive and comparative analysis using SPSS. Two hundred and nineteen patients (17.5%) met inclusion criteria with 51 (23.3%) patients positive for NRBCs. The presence of NRBCs had an increased mortality rate with an odds ratio of 6.0 (P = .001; 2.5, 14.5); was more likely to appear in older patients (P < .001); and was associated with increased hospital length of stay (P < .001), injury severity scores (P < .001), and complications. The presence of NRBCs even at the low concentrations reported in our study showed a 6-fold increase in the rate of mortality. With the current improvements in burn care leading to higher survival rates, the need to improve upon the numerous models that have been developed to predict mortality in severe burn patients is clear given the significantly increased risk of death that the presence of NRBCs portends.

Bilateral Lower Limb Salvage after Fourth-degree Burns: Subscapular Axis Free and Chimeric Flaps Effectiveness in Complex Reconstruction

Microsurgery is usually required for reconstruction of complex lower limb defects, preserving otherwise unsalvageable injuries. Fourth-degree burns are severe traumatic injuries. A case of bilateral lower limb salvage through a resourceful use of subscapular axis free and chimeric flaps for acute burn reconstruction of extensive lower leg injuries is reported. A 48-year-old man sustained a 40% surface area flame burn, circumferential and full-thickness at the lower limbs. Debridement of fourth-degree burns of the anterior lower legs resulted in bone exposure of the left and right tibias, right medial malleolus, and Achilles tendon. A latissimus dorsi (LD) flap plus a chimeric subscapular axis free flap with 3 components (LD, serratus anterior (SA), and parascapular) were designed for reconstruction. LD insetting for left tibia coverage with anastomoses to anterior tibial vessels was performed. Right side flap insetting provided tibia coverage with LD; medial malleolus with SA; and Achilles tendon with parascapular flap. An anatomical variation required anastomoses to proximal (chimeric LD + SA) and distal (parascapular) ends of posterior tibial vessels because of an independent origin of the pedicles. At 10-months follow-up after intensive rehabilitation, the patient showed proper functional outcomes at daily-life and work activities with autonomous walking using a single crutch. This case highlights the importance of microsurgery and chimeric flaps for limb salvage in extreme situations. The authors review and discuss the surgical options, emphasizing specific considerations of microsurgical reconstruction in burn patients.

The Added Benefit of Combining Laser Doppler Imaging With Clinical Evaluation in Determining the Need for Excision of Indeterminate-Depth Burn Wounds

Background Managing indeterminate-depth burn wounds remains challenging. Laser Doppler Imaging (LDI) has been validated for burn wound depth and can influence the clinical assessment. Our study investigated the value of LDI as an adjunct in determining the need for excision. Methods Seventy American Burn Association (ABA)-verified burn centers were surveyed. A controlled pre-test assessment without LDI and post-test assessment with LDI of 100 indeterminate-depth burn wounds was conducted to evaluate the influence on the clinical judgment among different health professionals. Relative risk, analysis of variance (ANOVA), paired t-test, and intention-to-treat were used for analysis. A p-value [Formula: see text] 0.05 was considered significant.  Results Among 32 burn centers, three confirmed using LDI. Six thousand grader-image interactions were analyzed. There was a significant difference in the predictive accuracy for pre-LDI and post-LDI assessments when all graders were considered (51.9% ± 7.0 vs. 72.9% ± 7.9; p < 0.0001). Post-LDI assessment added 20.9% more accuracy than the pre-LDI assessment. The post-LDI assessment was 1.4 times more likely to correctly predict the need for excision and skin-grafting than the pre-LDI assessment. All groups had an improved performance post-LDI: Group 1 (physicians), 51.9 ± 7.5 versus 76.4±5; Group 2 (nurses), 52.1 ± 6.1 versus 72.7±7.7; and Group 3 (others), 51.7 ± 9.2 versus 68.6 ± 10.1. No statistical difference was observed between groups (p = 0.92).  Conclusion LDI makes the clinical examination of indeterminate-depth burn wounds more accurate. For every five LDI evaluations performed, one assessor changed their treatment plan as a result of this imaging technique. LDI is cost-effective and increases the accuracy of determining the severity of indeterminate-depth burn wounds.

A Critical Update of the Assessment and Acute Management of Patients with Severe Burns

Significance: Burns are debilitating, life threatening, and difficult to assess and manage. Recent advances in assessment and management have occurred since a comprehensive review of the care of patients with severe burns was last published, which may influence research and clinical practice. Recent Advances: Recent advances have occurred in the understanding of burn pathophysiology, which has led to the identification of potential biomarkers of burn severity, such as protein C. There is new evidence about the potential superiority of natural colloids over crystalloids during fluid resuscitation, and new evidence about components of initial and perioperative management, including an improved understanding of pain following burns. Critical Issues: The limitations of the clinical examination highlight the need for imaging and biomarkers to assist in estimations of burn severity. Fluid resuscitation reduces mortality, although there is conjecture over the ideal method. The subsequent perioperative period is associated with significant morbidity and the evidence for preventing and treating pain, infection, and fluid overload while maximizing wound healing potential is described. Future Directions: Promising developments are ongoing in imaging technology, histopathology, biomarkers, and wound healing adjuncts such as hyperbaric oxygen therapy, topical negative pressure therapy, stem cell treatments, and skin substitutes. The greatest benefit from further research on management of patients with burns would most likely be derived from the elucidation of optimal fluid resuscitation protocols, pain management protocols, and surgical techniques from randomized controlled trials.

Feasibility of Pure Silk for the Treatment of Large Superficial Burn Wounds Covering Over 10% of the Total Body Surface

Large, superficial burn wounds require many painful dressing changes and, thus, dressings that can stay on the wound and peel off during re-epithelization such as Biobrane® and Suprathel® are preferred, but they are costly. Natural silk has shown good outcomes with respect to wound healing, scarring, and patient satisfaction. This study aimed to evaluate the efficacy of natural silk compared with that of initially used dressings for the treatment of superficial burn wounds greater than 10% of the TBSA. Patients with superficial burns covering &gt;10% of the TBSA were treated with pure silk for the first time (treatment group). Complications during wound healing with respect to the need for further surgery and scarring were compared with those of patients with similar burns of more than 10% TBSA and treated with nylon mesh and collagen instead of silk (treatment group). The treatment and control group comprised 25 and 13 patients, respectively. In total, 88% of patients in the treatment group did not require further treatment, while two patients with chemical burns needed further surgeries. Moreover, patients reported high satisfaction with respect to scarring and aesthetic outcome. Meanwhile, 85% of patients in the control group healed without further surgery and showed higher median hypopigmentation and hyperpigmentation after 12 months. Silk is an effective wound dressing for the treatment of large superficial burn wounds. It avoids painful dressing changes and yields satisfactory aesthetic outcomes. However, especially in large burns, careful initial wound depth assessment is crucial to prevent infection and reoperations.

Chemical mismanagement and skin burns among hospitalized and outpatient department patients

Purpose. This article attempts to elucidate the nature of chemicals causing major and minor skin burns, and their associated characterization across different industries, using Fujian provincial hospitals' admission and outpatient department records. Materials and methods. Data were collected from the provincial hospitals of Fujian through a questionnaire, sent via email, from June 1, 2017 to November 30, 2017. The collected responses were statistically analyzed using SPSS version 19 through the interquartile range, median, Mann-Whitney U test and Fisher's exact test with two-tailed significance. Results and conclusions. The results of 306 collected responses reveal that the majority of skin burn cases are due to a lack of technical education and professional training among workers handling chemicals. This study suggests that management's effective supervision and governmental regulations may help to prevent chemical skin burns at work, and can further be controlled by hiring professional workers alongside providing training to them in chemical handling as well as using protective equipment and developing appropriate management policies to improve victims' well-being and quality of life. Findings will help workers, doctors, hospitals, industries, government and other stakeholders to understand and control chemical hazards on site to minimize the risks of chemical skin burn incidents.

Skin bioprinting: the future of burn wound reconstruction?

Burns are a significant cause of trauma, and over the years, the focus of patient care has shifted from just survival to facilitation of improved functional outcomes. Typically, burn treatment, especially in the case of extensive burn injuries, involves surgical excision of injured skin and reconstruction of the burn injury with the aid of skin substitutes. Conventional skin substitutes do not contain all skin cell types and do not facilitate recapitulation of native skin physiology. Three-dimensional (3D) bioprinting for reconstruction of burn injuries involves layer-by-layer deposition of cells along with scaffolding materials over the injured areas. Skin bioprinting can be done either in situ or in vitro. Both these approaches are similar except for the site of printing and tissue maturation. There are technological and regulatory challenges that need to be overcome for clinical translation of bioprinted skin for burn reconstruction. However, the use of bioprinting for skin reconstruction following burns is promising; bioprinting will enable accurate placement of cell types and precise and reproducible fabrication of constructs to replace the injured or damaged sites. Overall, 3D bioprinting is a very transformative technology, and its use for wound reconstruction will lead to a paradigm shift in patient outcomes. In this review, we aim to introduce bioprinting, the different stages involved, in vitro and in vivo skin bioprinting, and the various clinical and regulatory challenges in adoption of this technology.

Mesenchymal Stromal Cell Preconditioning: The Next Step Toward a Customized Treatment For Severe Burn

Over the last century, the clinical management of severe skin burns significantly progressed with the development of burn care units, topical antimicrobials, resuscitation methods, early eschar excision surgeries, and skin grafts. Despite these considerable advances, the present treatment of severe burns remains burdensome, and patients are highly susceptible to skin engraftment failure, infections, organ dysfunction, and hypertrophic scarring. Recent researches have focused on mesenchymal stromal cell (MSC) therapy and hold great promises for tissue repair, as reported in several animal studies and clinical cases. In the present review, we will provide an up-to-date outlook of the pathophysiology of severe skin burns, clinical treatment modalities and current limitations. We will then focus on MSCs and their potential in the burn wound healing both in in vitro and in vivo studies. A specific attention will be paid to the cell preconditioning approach, as a means of improving the MSC efficacy in the treatment of major skin burns. In particular, we will debate how several preconditioning cues would modulate the MSC properties to better match up with the burn pathophysiology in the course of the cell therapy. Finally, we will discuss the clinical interest and feasibility of a MSC-based therapy in comparison to their paracrine derivatives, including microvesicles and conditioned media for the treatment of major skin burn injuries.

Advancements in Regenerative Strategies Through the Continuum of Burn Care

Burns are caused by several mechanisms including flame, scald, chemical, electrical, and ionizing and non-ionizing radiation. Approximately half a million burn cases are registered annually, of which 40 thousand patients are hospitalized and receive definitive treatment. Burn care is very resource intensive as the treatment regimens and length of hospitalization are substantial. Burn wounds are classified based on depth as superficial (first degree), partial-thickness (second degree), or full-thickness (third degree), which determines the treatment necessary for successful healing. The goal of burn wound care is to fully restore the barrier function of the tissue as quickly as possible while minimizing infection, scarring, and contracture. The aim of this review is to highlight how tissue engineering and regenerative medicine strategies are being used to address the unique challenges of burn wound healing and define the current gaps in care for both partial- and full-thickness burn injuries. This review will present the current standard of care (SOC) and provide information on various treatment options that have been tested pre-clinically or are currently in clinical trials. Due to the complexity of burn wound healing compared to other skin injuries, burn specific treatment regimens must be developed. Recently, tissue engineering and regenerative medicine strategies have been developed to improve skin regeneration that can restore normal skin physiology and limit adverse outcomes, such as infection, delayed re-epithelialization, and scarring. Our emphasis will be centered on how current clinical and pre-clinical research of pharmacological agents, biomaterials, and cellular-based therapies can be applied throughout the continuum of burn care by targeting the stages of wound healing: hemostasis, inflammation, cell proliferation, and matrix remodeling.